New IBM technology allows consumers to pay for their in-store products using their smart phones. The company launched the self-checkout system last week at the National Retail Federation's Big Show in New York City.

We stopped by the booth to get a hands-on demonstration and learned that shoppers' phones will be assigned 2-D barcodes that hold the personal information needed to conduct transactions. Barcodes also track buying history and info for loyalty programs.

To pay by phone, shoppers must scan their products as they shop and then scan the 2-D barcodes (on their phones) at the self-checkout lane.

Click here to watch a demo.